Question

Troubleshooting 93 GMC Sonoma 4.3L v6.

My daughter was driving down the road the accelerator stopped working and the brakes got really stiff, so she pulled over and turned the truck off, after she tried to restart the truck it would not start back up. I do not know if this is related to the problem we have ,but, the other day I had to replace a fuse for the horn and interior lights, which blew out again as well, I checked the fuse for the fuel pump it was good, n replaced the blown horn/interior lights one. Could this be the fuel pump quiting or something electronic related as to why the truck will not restart? What puzzles me is she said the truck was still running when she shut it down so I'm wondering if the fuel pump is not the problem but something else that would cause it to stop accelerating and for the brakes to get suddenly stiff. Any ideas or suggestions would be greatly appreciated, Thanks.

Well maybe she got a bit frazzled when all this happened, but it sure sounds like the engine just quit running. My feeling is that we always accept the simplest answer first before going off into the esoteric realm=== and really, an engine stall fully explains the symtoms.

If the fuel pump relay failed, the oil pressure switch would have powered the fuel pump anyway (in theory).

Anyway, you could squirt some starting fluid into the intake system to see if the engine runs momentarily. If it does, then you must have some fuel delivery issue. You could use a fuel pressure gauge to test pressure in the fuel rail, and you could check the fuel pump relay. Sometimes if you read the part # on the relay you can find another one in the array to switch off with that one, for testing purposes.